离子膜电解槽阳极阴极涂层 IEM Anode Cathode Coating

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1°UHDENORA-DENORA Chlorine Symposium Suzhou March 2008

IEM Anode and Cathode

Coating Operation

离子膜电解阴极和阳极涂层

March 08

2AGENDA

要讨论的话题Importance of Coatings.

涂层的重要性Causes of Coating Failure.

涂层失效的原因

How Maintain good coating performances all along the guaranteed life.

在寿命保证期内，如何保持好的涂层性能Measuring the Residual coating load.检测剩余的涂层

Measuring coating and membrane condition during the operation.

在电槽操作期间，检测涂层及膜的状况

A good Anode coating:

好的阳极涂层

9Keeps your plant in business, with a very flat cell voltage profile over 8 years.

可在保证期八年时间内，维持平稳的电槽电压。

A good Cathode coating:

好的阴极涂层

9Reduces hydrogen overvoltage by more than 200 mV over bare nickel.

相对于无涂层的镍，阴极涂层可降低氢过电位200mV 以上

A Bad Anode Coating:坏的阳极涂层

9Will cause a very sharp voltage increase in a short period of time up to the point where plant has to be shut down.

可在短时间内造成槽电压迅速上升，直至使电槽被迫停车A Bad Cathode coating:坏的阴极涂层

9Will cause a quick increase of the cell voltage of about 100/150 mV: every 100 mV increase is

equivalent to ~ 3% increase in power cost.

会导致槽电压快速上升100~150mV; 槽电压上升

100mV,电耗约增3%

Causes of Anode and Cathode Coating Failure 阴、阳极涂层失效的原因

6

Anode coating failure can be caused by some impurities present in the feed brine such as:

盐水中的一些杂质会导致阳极涂层失效

Fluoride: Parts per million levels in brine will strip the DSA®coatings to bare Ti in hours.

氟：盐水中ppm级的氟也会在数小时内使涂层脱落

Manganese: Will cover existing DSA®catalyst with pseudo-catalytic coating which is almost impossible to remove.

锰：会覆盖掉阳极活性涂层，形成一层伪涂层，且几乎不可能除去

Barium/Strontium/Silica: Form tenacious deposits which are very difficult to remove.

钡/锶/硅：会沉积在活性涂层表面，且很难除去

阳极涂层失效的原因

Other possible reason of anode coating failure are:

其它可能导致阳极涂层失效的因素：

Caustic back-migration:碱的反向迁移

9OH-ion back-migration through membrane scratch.

OH -离子通过膜的划伤部位反向迁移

9OH-ion back-migration through membrane pin hole.

OH -离子通过膜上的小孔反向迁移

9Tear in the membrane.

OH

-离子通过撕裂的膜反向迁移Normal coating ageing:正常的涂层的老化

9Occurs after years of anode service.使用数年后，涂层会渐渐老化9Difficult to detect.这种情况很难探测

9Requires regeneration (recoating) of the substrate or mesh replacement.必须进行重涂或换活性网

阳极涂层失效的原因

8 Cathode coating failure can be caused by:

阴极涂层的失效可能由下列原因造成：

High Fe content in the catholyte:

阴极液中含铁太高

9Fe deposition on the cathode will cause an

over coating layer that reduces the cathode

coating activity.

Fe在阴极表面沉积形成覆盖层，会导致阴极活性降低阴极涂层的失效